Summary The Mandarin Arrowwas en route from Kitimat, British Columbia, to Duncan Bay, British Columbia, under the conduct of a British Columbia coast pilot. During the approach to a wharf in Duncan Bay, with two tugboats assisting, the vessel grounded approximately 25metres from shore. The pilot notified the authorities, while the master and crew carried out damage assessment. Approximately 55 minutes later, the vessel refloated on a rising tide and was berthed at the wharf without further incident. The vessel remained alongside the berth while temporary repairs were completed. No injury or pollution was reported as a result of this occurrence. However, the Mandarin Arrow sustained extensive damage to her shell plating. Ce rapport est galement disponible en franais. Other Factual Information Particulars of the Vessel Description of the Vessel The Mandarin Arrow is a general cargo vessel with 10 cargo hatches and two moveable gantry cranes. The wheelhouse, machinery, and accommodations are all housed in one superstructure located at the after end of the vessel. The distances from the superstructure to the vessel's bow and stern are approximately 170m and 30m, respectively. The wheelhouse has an open layout, with the steering console recessed in the middle and the chart table behind the steering console. A gyro repeater with azimuth mirror is located on each bridge wing and a third is mounted in the wheelhouse, on the forward bulkhead, in the centre line. Two radars and consoles with various controls are located next to the forward bulkhead. One radar is mounted to the left, and the second radar and pulpit with engine controls is to the right of the wheelhouse gyro repeater. The clock and the vessel's speed and revolutions per minute (r/min) indicators are mounted on the forward bulkhead in front of the steering console. The rudder indicator is located on the deckhead in front of the steering column and is easily visible from every position inside or outside the wheelhouse. The propulsion machinery of the Mandarin Arrowconsists of one reversible main engine driving one right-handed, fixed-pitch propeller. It may be controlled either from the engine control room or directly from the wheelhouse or from either bridge-wing. At the time of the occurrence, the wheelhouse-control mode was in use. The vessel is fitted with a 2040brake horsepower bow thruster and Schilling rudder; the latter, when fully deflected, renders the effect of a stern thruster. Reportedly, both were used by the bridge team prior to and during the occurrence. Description of the Site Duncan Bay is a body of water in Johnstone Strait lying approximately four miles south of Seymour Narrows. It is bounded by Vancouver Island to the west and open to the northeast. Located in Duncan Bay is a large pulp and paper mill which owns and manages three wharves: a pulp wharf, a paper wharf, and a barge-loading facility. The pulp wharf, to which the Mandarin Arrow was allocated, is 152 m long and extends into the bay at 15degrees True (T), almost parallel to the shore; it has a mooring dolphin located at its north end (see Appendix A). History of the Voyage The Mandarin Arrowdeparted Kitimat partially loaded on 16 August 1999 at 0200. Her deadweight was 28685tonnes (t); her total displacement was 43510t. With two British Columbia (B.C.) coast pilots on board, the vessel proceeded to Duncan Bay. The trip along the B.C. coast was uneventful; the pilots took turns conning the vessel while the master and crew performed their normal duties. On August 17, shortly after 0400, she transited Seymour Narrows. After passing Race Point at 0436, the pilot began slow-steaming the vessel in order to approach the berth not sooner than 0600 (as the shore linesmen were not available before this time). The quartermaster was hand-steering; the master and officer of the watch (OOW) were also in the wheelhouse. As the distance to go was only about two and a half miles, the speed was reduced substantially, and the engines were stopped occasionally. To maintain steerage at this low speed, the bridge team used the bow thruster. This was handled by the OOW, while the master oversaw the performance of both the vessel and bridge team. While it was slow-steaming, the vessel reportedly remained to the west of the wharf's axis, and the pilot observed that the current, which had just turned to flood, was setting slightly in a southwesterly direction. At 0520 two tugboats, the Regentand the Seymour Crown, arrived to assist the Mandarin Arrow in the final approach to the pulp wharf. Neither the Regent nor the Seymour Crown are dedicated docking tugs. They perform this task when available and when not engaged in other regular towing duties. Reportedly, the pilot receiving information from one of the tugboats that the current set near the wharf's outer end was not significant. He ordered the Seymour Crown to the vessel's port quarter and the Regent to stand-by off the starboard bow and await orders - with both being ready to push. The crew on the bow was instructed to walk out the starboard anchor to above the water level and leave it in gear. The master considered both these orders to be standard precautionary measures. When the Mandarin Arrowwas approximately four cables from the dolphin, on a heading of about 120T, the pilot initiated a starboard turn towards the berth. At the same time, the current began to set the vessel southward. When the Mandarin Arrowwas almost parallel to the wharf with the bow approximately 100m from the dolphin, the pilot attempted to stop the turn but the starboard swing continued. Simultaneously, the vessel was rapidly setting bodily towards the rocky shoal on her port side. It appeared that the hull was pivoting clockwise around the bow. The pilot ordered the stand-by tug to go to the port quarter and both tugs to push on the vessel's port side. The bow thruster was set to thrust the bow to starboard with full power and the starboard anchor was let go with approximately 25m of cable. The rudder was moved hard to port which, with the propeller working ahead, was intended to arrest the swing and move the stern away from danger. When these countermeasures were observed to be having no effect, both the master and the pilot decided to abort the approach and reversed the engine to withdraw the vessel, stern first. The engine was reversed, first at 51r/min and then, gradually over the following two minutes, this was increased to 85r/min. However, before the vessel could begin to move astern, she swung to approximately 268T, touched the ground, and then swung back and stopped on a heading of 233T. Immediately after the vessel went aground, the pilot notified the authorities and ordered an additional tugboat sent to the site of the grounding. The master and the crew began implementing damage assessment and pollution control measures. All tanks and bilges were checked. It was established that the contact with the bottom was made by the vessel's port side hull in the vicinity of holds Nos2 and 3. At approximately 0552 the requested third tugboat arrived and, after some ballast water was pumped out, the vessel was fully refloated at 0630 on a rising tide. The subsequent berthing operation was uneventful, and the Mandarin Arrowberthed port side to the pulp wharf at 0742. Course Recorder, Event Log, and Compass The vessel's course recorder interfaced with gyrocompass shows that the course steered between approximately 0438 and 0520 oscillated about the heading of 150T. From 0520 till 0524, the vessel turned to port until the heading reached 128T, thence she momentarily veered to starboard. At approximately 0536, the heading reached 268T. Subsequently she swung back to port until the heading steadied at 233T at 0540 for approximately 55minutes while the vessel was grounded. The vessel's event log shows the following engine movements: The Bell Book contains the following pertinent entries: Damage Shortly after berthing, a team of divers, surveyors, and owners' representatives began damage assessment, and an underwater video was taken. Bottom plating indentations were found along port side wing water ballast tanks Nos 1, 2, and 3. The port side bilge keel was bent and the bilge strake between frames162 and 163 was found fractured, with rocks inserted in the crack. As requested by Transport Canada Marine Safety and classification society surveyors, temporary repairs were carried out while the vessel was conducting loading operations alongside the pulp wharf. The most serious damage - fracture of tank No3 - was provisionally covered with an outside cement box. At 1048 on August 18 the Mandarin Arrow sailed for Nanaimo, B.C. On August19 she departed Nanaimo and arrived in Vancouver, where the repairs were completed. A steel box was welded inside tank No 3 to cover the fracture. After the repairs had been completed, the vessel obtained a Seaworthiness Certificate and sailed to her destination in Europe on August23. There were no injuries or pollution as a result of this occurrence. Certification Vessel At the time of the occurrence, all the vessel's certificates were valid. A Cargo Ship Safety Certificate was issued by Det Norske Veritas in Oslo, Norway, on 20 November 1998. The last Port State Control Inspection was conducted in China on 5 April 1999; no deficiencies were found. She was last dry-docked in Ulsan, Korea, in April 1999. Vessel Personnel The master of the Mandarin Arrowheld a Master Foreign Going Certificate of Competency, issued in the United Kingdom in 1979, and renewed in 1998. He had 30years of sea service on various cargo vessels in worldwide trade, including 18years as master. Since 1991 he had served as master with the owners of the Mandarin Arrow. During the three years previous to this occurrence, he served as master of this vessel on a four-months-on/four-months-off basis. The Chief Officer, who was performing wheelhouse duties during the occurrence, held a Master Mariner's Certificate of Competency issued in Manila on 4 November 1998. He had accumulated approximately 13 years of sea time, approximately three of which were as Chief Officer. The two remaining deck officers on board the Mandarin Arrow held competency certificates of appropriate grades. Pilot The pilot held a Canadian Master Mariner's Certificate of Competency, issued in 1982, and a Pilot's Licence class 1, issued in 1996. He had attended all the required upgrading courses: automatic radar plotting aid (ARPA); radar; marine emergency duties (MED); and shiphandling. Up to 1995 he accumulated a total sea time of approximately 28years on various Canadian tugboats and Coast Guard vessels. Since 1995 he had piloted a wide range of cargo vessels through most of the navigable waters of the B.C. coast, including several trips to and from Duncan Bay. He completed a bridge resource management (BRM) course in June 1997. Prior to becoming a pilot, for a number of years he had operated a fleet of fish packers from Brown Bay (six miles to the north) and was in and out of Duncan Bay on a regular basis. Fatigue The Mandarin Arrow arrived Kitimat at 0214, August 11, and departed August 16 at 0200. After departure, the watch standing officers of the Mandarin Arrowperformed their normal shipboard duties. During the five days in port the master was afforded the time to rest. After the departure from Kitimat, due to intermittent fog experienced during the passage, he was required several times on the bridge in addition to conducting his other duties. He slept between 0400 and 0700 on August16, and again between 1300 and 1500. He was called to the bridge from 1900 until 2030 with a further rest between 2030 and 2200. After 2200 he was on the bridge until arrival at Duncan Bay on the morning of August 17, giving a total of 6hours sleep in the 28-hour period from departing Kitimat. Although the master's circadian rhythm had been disrupted, and the accident happened at 0540, less than eight hours had elapsed since his last rest and his 72-hour sleep history does not suggest a sleep debt. The pilotage during the passage was shared equally between the two pilots, each of whom rested when not conning. Weather and Current Information The weather throughout the passage from Kitimat to Duncan Bay was described as cloudy with occasional fog patches. During the approach to the berth, there was a very light wind, a calm sea surface, and very good visibility. Duncan Bay is subject to large mixed-type tides that generate strong reversible currents. The Canadian Sailing Directions for B.C. Coast, Southern Portion warns mariners: In navigating the coast where the tidal range is considerable, caution is always necessary . . . . Arrows on charts show the usual or the mean direction of a tidal stream or current. It must never be assumed that the direction of the stream will not vary from that indicated by the arrow. Oceanography of the British Columbia Coast 2states that Johnstone Strait is: . . . characterized by swift and rectilinear tidal currents. In the vicinity of shallow sills and constricted narrows, surface currents are accelerated even further, and take on a turbulent jetlike nature, generally associated with quasi-permanent tidelines that delineate rapid cross-stream changes in speed and direction of the set. The same publication refers to Seymour Narrows: . . . as an illustration of the maximum strength attainable by tidal currents in the world ocean and to demonstrate their hazard to navigation . . . It states that the waters in the vicinity of and south of the Narrows are especially affected by the tidal currents. Canadian Hydrographic Service (CHS) charts used on board the Mandarin Arrow - CHS3539 and CHS3540- show several arrows delineating the currents during flooding and ebbing phases of the tide (see Appendix A). One arrow is placed just north of the pulp wharf in Duncan Bay. It shows the ebbing current in an easterly direction. There is no matching arrow referring to the flooding current in the vicinity of the wharf, although all other references to the tidal currents on the chart are paired. According to the Canadian Tide and Current Tables, Volume6, the tide at Duncan Bay was rising at the time of the occurrence, with low water predicted to be at 0435, and high water at 1032 (see Appendix B). This suggests the beginning of a flooding current; however, according to information obtained from the CHS, the current flow in Discovery Passage is driven by the difference in water level between the Strait of Georgia and Johnstone Strait. The relationship between the water level in Duncan Bay and the current in Discovery Passage is a complex and unpredictable one; the state of one cannot be inferred from the state of the other. The CHS Geomatic Engineering Branch monitors and analyses the tides and currents in Canadian waters. In reference to Duncan Bay, it states that the transition period between ebb and flood may show large flow variations as the new pattern is established. The arrows shown on the charts only hold true once the ebb or flood is fully established. The absence of arrows does not imply the absence of significant currents. The Pacific Pilotage Authority (PPA) has acknowledged that currents can create difficulties for large deep-sea vessels berthing in Duncan Bay. On 24September 1993 the PPA issued a memo to shipping agents and coast pilots in which it recommended that, due to the extreme and unpredictable nature of the currents, the accessory horsepower for berthing in Duncan Bay be 50 percent greater than that normally required for docking and undocking. A rule of thumb is a minimum of five percent of the vessel's registered summer deadweight, converted to horsepower. Consequently, the PPA memo recommends that the numeral denoting accessory power for Duncan Bay be 7.5 percent of the numeral indicating a vessel's summer deadweight. The summer deadweight of the Mandarin Arrowis 51 733 t. The Regent and Seymour Crownhave 1050 and 730 brake horsepower, respectively; the vessel's bow thruster is rated as having 2040 brake horsepower. Thus, the combined horsepower of the tugs and the bow thruster was 3820, approximately 7.4percent of the vessel's summer deadweight. Previous Incidents During berthing in Duncan Bay in August 1994, the Star Evangerwas suddenly set eastward; it struck and heavily damaged the pulp wharf. The TSB investigation into that occurrence found that a subsurface current was acting on the vessel, causing her to move sideways. 3 Since 1974, 22 instances of a deep sea vessel striking a wharf while berthing in Duncan Bay have been recorded. Each of these strikings, like the grounding of the Mandarin Arrow, originated with a sudden set or a swing of the manoeuvring vessel caused by currents. (On only two occasions was wind considered to have been a factor.) In these occurrences, the current was at various stages when the sudden surge hit the vessel; collectively, they show no consistent pattern of the set that could be linked with the tide in Duncan Bay, or with the known current stage in nearby waters.